Plant species characteristic of arid and semi-arid zones, such as Argania spinosa (L.) Skeels, have a taproot that allows them to reach the soil horizons more quickly. Unfortunately, in the nursery, the containers of culture used for the production of seedlings do not support an excellent development of the root architecture that can be able to resist the shock of transplantation, in particular of the hydric stress. This study aimed to evaluate the physiological and biochemical behavior of Argania spinosa seedlings grown in containers of different depths under water stress. An experiment was conducted with 90 seedlings from the different containers (P1 for depth of 16 cm, P2 for depth of 30 cm, and P3 for depth of 60 cm), and three watering treatments (well-watered 100% of field capacity, moderate stress with 50% of field capacity and severe stress with 25% of the field capacity). Our results showed that seedlings from the 16 cm container had lower values of water status. Malondialdehyde content, electrolyte leakage, hydrogen peroxide, and superoxide radical content gave higher values on seedlings from the shallow container. The benefits of increasing the container depth of nursery seedlings contribute to the improvement of physiological and biochemical responses of seedlings under water stress. To fully validate our findings, a long-term field study must be conducted.

Aim of study:The objective of this study was to optimize the germination of A. spinosa seeds after different physical pretreatments by thermal shock to establish a simple, effective, and less expensive procedure.Area of study: The study was conducted in the laboratory on seeds from four regions of Morocco (Aoulouz, Essaouira, Sidi Bou Othmane, and Boulaouane).Material and methods: The seeds were dried and stored. Before the launching of the experimental protocol, they were dehulled and applied each their pre-treatment for the four provenances. The pretreatment used are the following. C: control without thermal shock, HC1: freezing, HC2: hot water, HC3: freezing + hot water.Main results: The results showed that the onset of germination of argan seeds subjected to pretreatment HC3 was reduced by 2 days on mean compared to seeds that were subjected to pretreatment (C). The application of the cold or hot pretreatment allowed us to reach up to 82% of the final percentage of germination. However, the combination of two pretreatments allowed us to reach up to 100% of the final germination percentage.Highlights: Freezing combined with hot water significantly improved the germination of A. spinosa seeds. This pretreatment could be recommended in the nursery for practitioners.

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